ERGONOMIC WORKPLACE DESIGN IN THE CLOTHING...

DAAAM INTERNATIONAL SCIENTIFIC BOOK 2014 pp. 109-120 Chapter 08

ERGONOMIC WORKPLACE DESIGN IN THE

CLOTHING SHOP

VUJICA H. N. & BUCHMEISTER, B.

Abstract: Introducing ergonomic principle into work is very important. Since work is

one of the basic factors of human life appropriate designed workplace can contribute

to healthy and satisfied worker. Beside that ergonomically designed workplace also

improves worker's efficiency at work and decreases the possibility of injuries. The

aim of the presented research was to determine whether the work area within a

chosen retail shop was safe and effective enough. The OWAS method was used aimed

to estimate the body postures during the working day. It was discovered that certain

body positions resulted in significant overload which meant that certain remedies

were necessary during the working process to prevent possible damage to the body.

As a result an innovative system with moving shelves was proposed in order to

prevent the shopkeeper from awkward body postures. Similar solutions can be found

in industrial warehouses and could solve problems that occur during overhead work. Key words: ergonomics, anthropometry, OWAS, strain and stress at work, workplace design

Authors´ data: Asist. Prof. Dr. Sc. Vujica Herzog, N[atasa], Assoc. Prof. Dr. Sc.

Buchmeister, B[orut]; University of Maribor, Faculty of Mechanical Engineering,

Smetanova ulica 17, 2000, Maribor, Slovenia, [email protected],

[email protected]

This Publication has to be referred as: Vujica Herzog, N[atasa] & Buchmeister,

B[orut] (2014). Ergonomic Workplace Design in the Clothing Shop, Chapter 08 in

DAAAM International Scientific Book 2014, pp.109-120, B. Katalinic (Ed.),

Published by DAAAM International, ISBN 978-3-901509-98-8, ISSN 1726-9687,

Vienna, Austria

DOI: 10.2507/daaam.scibook.2014.08

Vujica Herzog, N. & Buchmeister, B.: Ergonomic Workplace Design in the Cloth...

1. Introduction

For successful workplace design several elements must be examined: space,

equipment, tools, auxiliary devices, etc. Of decisive importance for healthy and

enjoyable jobs is a neat and organized workplace that must be sufficiently spacious,

airy, bright, and comfortable. Lighting is of significant importance as it provides

contrast between the working and surrounding areas. Lighting should shed enough

light yet should not adversely affect the sight of the user. On the other hand, its noise

should not disturb composure and communication. The workplace’s size and shape

must therefore be adapted to a human’s working activities to allow him/her as many

comfortable working postures as possible.

In addition, safety within the workplace must be ensured whilst working in order

to preserve the health of the worker. Working systems differ from each other but

what they have in common is that they are formed as a result of conscientious,

systematic, and creative human efforts.

The purpose of this research work was to point out that a well-ordered

workplace provides a pleasant atmosphere that at the same time encourages greater

productivity from the worker. In this way it is possible to achieve an enjoyable

workplace for the worker with minimum body stress, which may affect his/her

physical and mental ability to work. The aim of the presented research work was

therefore to conclude whether the chosen workplace was effective enough, and if

potential changes to that workplace were needed or possible.

Using the current observation method it can be evaluated whether certain parts

of the body are experiencing too much stress, which means that necessary actions are

needed in order to reduce the body’s overload. Namely, stresses on certain parts of

the body reduce a human’s ability to be effective while working. Therefore it is very

important that the workplace, in the textile industry also, is optimized in such a way

that e.g. desks, chairs, and appliances are constructed and installed well, in order to

prevent bad positions of the human's body.

Ergonomics deals with the exploration of human physical and mental

capabilities during working and adjusting the working load. By using ergonomic

arrangement of the workplace it is possible to adapt work to a human’s physical and

mental characteristics and to reduce or prevent adverse effects on health. Correct

designing of the workplace also includes human habits to ensure humans’ work as

productively effectively, and safely as possible.

The two most important factors that influence stress at work can be divided into:

Working environments with working conditions such as noise, heat, humidity,

illumination, air velocity and

Body postures; especially awkward postures that can cause health problems. The

OWAS observation method can be used for posture analyses.


2. Literature review

Work-related musculoskeletal disorders have been increasing within

manufacturing and services. As these injuries impose high costs for companies

(worker absence, manufacturing losses, delays…) and society (high costs of medical

treatment), it is important to prevent them through ergonomic assessment and job

redesigning.

One of the more significant contributory factors of neck and shoulder pains is

when working with arms above shoulder height, which is referred to as 'overhead

work' (Aghazadeh et al., 2012; Grieve & Dickersond, 2008; Garg et al., 2006;

Nussbaum et al., 2001; Spyropoulus et al., 2013). Overhead work can be found

within various occupations and industries such as healthcare, nursing, automobile

manufacturing, mining, welding and maintenance/repair work (Rosecrance et al.,

2006; Harcombe et al., 2006; Warming et al., 2009). Workers in these occupations

suffer from neck and shoulder pains, discomfort, and limited productivity. Aghazadeh

and other authors (2012) studied the effect of overhead lifting on neck and shoulder

muscle activities and upper extremity joint angles. They quantified the relationships

between the upper extremity joint angles and neck muscle activity during overhead

lifting. The results showed that shoulder angles had a significant influence on neck

muscle activity; this was because as the shoulder angles increased, the neck muscle

activity also increased. The results indicated that lifting with elevated arms should be

avoided, especially when heavy weights are being lifted.

Various strains and stresses reduce human efficiency at work due to disturbed

haemostasis, thus resulting in fatigue. In order to reduce the effects of this

phenomenon, working hours should be interrupted by several rest periods and breaks

(Nussbaum et al., 2001; Spyropoulus et al., 2013). In addition the workplace should

be designed using anthropometric measures, in regard to human dimensions (Polajnar

et al., 2010).

3. Methodology

The following steps were taken for considering the presented problem.

Workplace analysis and evaluation; analysis of the existent workstation

dimensions with respect to working postures and workers’ perceptions; the

saleswoman in a store 7’ Camicie observation. The observation was conducted

over two days, 3 hours per day, 6 working-hours altogether.

Workplace analysis by considering the working environment; accurate

measurements were taken of noise, illumination, heat, humidity, and air

velocity.

The extended OWAS method was used at nursing workstations to evaluate the

strains caused by different operators’ postures.


The examined workplace was designed and analysed using the Jack software

package created by Technomatics.

Comparison between manually-performed OWAS analysis and software OWAS

analysis was made to confirm the reliability of the performed research,

Based on the results of OWAS analysis certain propositions were advanced for

improving working conditions and preventing possible health problems in the

future.

4. Workplace observation

4.1 Clothing shop 7 ' Camicie

7 ' Camicie is a recognized Italian clothing brand known for its glamour, quality,

and versatility. It is suitable for men who love elegance, as well as for women who

like to display their ambitions (Fig. 1).

Fig. 1. 7 ' Camicie shop Fig. 2. 7 ' Camicie shop's lighting

As is seen from (Fig. 2) the shop is equipped with general lighting. The

saleswoman performed mainly standing work (Fig. 3). Whilst loading the material

onto shelves or taking them down for the customers she uses a ladder. The posture

position is dangerous as the saleswoman must remain on the ladder and reach-up for

the desired piece with one or both arms above her shoulder. Ladders must be used

securely so that they cannot slip, be tipped-over or malfunction. When the ladder is

used, the woman must stand with both feet on the same rung of the ladder (Fig. 4).

Microclimatic parameters are important factors in the physical environment

which significantly affect the conditions of the working environment (Andrejiova et

al., 2012). These parameters significantly affect the welfare of working people and

should be verified regularly. Two different measuring devices were used during the

experiment. The noise was measured using Voltcraft SL-100 noise-meter (Fig. 5 - a).


Other measurements such as illumination, heat and air velocity were taken using the

Testo 435 multifunctional device (Fig. 5 - b).

Fig. 3. The prevalent working position

Fig. 4. Uploading the material onto the shelves with the help of a ladder

a. b.

Fig. 5. Measuring devices


4.2 OWAS method

The OWAS method (Ovaco Working Analysing System) is a method of posture

monitoring. This method originated from Finland's steel industry where body the

positions of workers were analyzed using an elaboration observation method called

OWAS. This method was initially successful and was therefore further developed and

modified. It is considered to be a practical method for identifying and evaluating

working postures. The OWAS procedure consists of two parts: an observational

technique for classifying body postures, and a set of criteria for the redesigning of

working methods and workplaces. Body postures are classified into 28 positions

including the positions of the back (four positions), upper limbs (four), hands (three),

lower limbs (nine), head and neck (five), as well as the load or force handled (three).

Each of these positions has pre-defined high risk and low risk postures that are

coded by the observer. After calculating the amount of time the worker maintains

these postures, the final step is to assign a four-level action code for task

improvement. These four action codes are defined as follows: changes are not

needed, changes needed in near future, changes needed immediately, need intensive

observation.

4.3 Computer-Aided OWAS analysis

In order to asses the presented workplace the ergonomic software package Jack

was used, as created by Siemens PLM. Jack is a complete system for generating 3D

environments and interacting with them within a powerful graphical environment. It

is based on a detailed link segment model with biologically accurate motion

prediction and joint kinematics. When using Jack we can design real-time

environment with interactive viewing, multiple windows, lights and cameras,

textures, and mirrors.

The most important and useful part of Jack software is the possibility of

performing different analyses. The Jack analysis toolkit is a set of Ergonomic

analysis tools that help us to design better work areas and evaluate physical tasks.

Some of the analyses are:

Lower back analysis tool,

Static Strength prediction,

NIOSH,

Metabolic energy expenditure,

Fatigue recovery,

Ovako Working Posture Analysis (OWAS) tool,

Rapid Upper Limb Assessment (RULA),

Manual handling limits,

Force solver,

Predetermined time.

By using different analyses Jack enables us to design a workplace that

minimises the risk of low back injuries, determines whether workers have enough

strength to perform their prescribed job,, design and evaluate lifting jobs, determine


the metabolic energy requirements of a job and compare alternative job designs based

on their relative risks of exposing workers to fatigue. In addition Jack help us when

assessing working postures for their potentials to expose workers to injury, identify

manual tasks that expose workers to increased risk of upper limb disorders, evaluate

manual handling tasks and predict whether a worker can be expected to perform a job

under predefined cyclical-time requirements.

We used Jack 7.0 for redesigning the workplace in 7 Camices' shop by

simulating working postures and above all to perform several analyses.

5. Workplace analyses and results

During the workplace analyses when considering working environment,

accurate measurements were taken of noise, illumination, heat, and air velocity, (Tab.

1). The measured values of temperature and air velocity were suitable for the

presented working environment. The noise level was also within the recommended

values. Space illumination was very high and the illumination effect was even higher

because of mirrors fitted onto the walls and therefore the illumination was magnified.

It is generally known from research performed within manufacturing that higher

illumination levels increase productivity and increase attentiveness that could also be

of benefit in a clothes shop.

Measured values

Noise

[dB]

Illumination

[lx]

Temp. [ºC] Air velocity [ms-1

]

63 1530 22.5 0.09

72 1520 23.2 0.14

59 1490 22.3 0.11

Average value 64.6 1513.3 22.7 0.11

Tab. 1. Noise level, illumination, temperature, and air velocity

When observing the working postures, the OWAS method was conducted over

two days, for 3 hours each day, altogether 6 working hours. In the Tables below (Tab.

2 and Fig. 7) the results of the body position monitoring can be seen. 248 (n = 248)

measurements were performed during 6 hours of working; approximately one record

per minute. The method of working was similar across the entire workday, so it can

be assumed that all possible positions that could be harmful for the worker were

observed and recorded.

Prior to starting the observation procedure we followed the worker and her body

positions. The results from our observations were recorded by drawing lines on a

particular form. On this basis we calculated the share of each physical situation and

the time of each body position. The calculations required the following information:

the sum of each body position (∑Fp), and the sum of all body positions within each


group of working positions (∑Fs). Equation 1 was used for calculating each body

posture.

(1)

Duration of a particular body position (tp) was calculated using Equation 2:

(2)

The obtained results were compared with the recommended measurements (Tab.

3) and the results are presented with signs in Tab. 2 and in the histogram (Fig. 7). As

can be deduced from the results and histogram where the allowed and recommended

values were recorded, there were overloads in the following body positions: 1.2 –

bent back, 2.3 – one arm above shoulder, 2.4 – both arms above shoulders, 4.3 –

standing on one leg, 5.2 – bent forward head and neck, 5.3 – bent to side head and

neck and 5.4 – bent backwards head and neck. According to OWAS positions

changes were needed for these positions in the near future.

Body

Parts

Thoraxlumb.

spine Upper limb Hands Lower limb Head

1.1 1.2 1.3 2.1 2.2 2.3 2.4 3.1 3.2 3.3 4.2 4.3 4.6 5.1 5.2 5.3 5.4 5.5

Nr. of

measur.

110 90 48 78 30 80 60 108 72 42 100 82 66 80 58 52 58 40

40.3 36.3 19.3 31.5 12.1 32.2 24.2 48.6 32.4 18.9 40.3 33.0 26.6 32.2 23.4 20.9 23.4 11.1

145.1 130.7 69.5 113.4 43.6 115.9 87.1 175 116.6 68.0 145.1 118.8 95.8 115.9 84.2 75.2 84.2 40

Measure

Tab. 2. OWAS – calculated results with recommended measures

5.1 Comparison with the computer performed OWAS method

Since manually performed OWAS method is time consuming and can be

annoying for a worker we decided to design and analyze workplace also using

computer simulations and analyses.

The results from computer-aided posture simulations confirmed the posture

problems discovered using the manually performed OWAS method. In regard to

those body postures of bent back, one arm above shoulder, both arms above shoulder,

standing on one leg, and all head positional changes were needed in the near future.


Fig. 7. The histogram of the OWAS results applied at the inspected workplace

Body

Parts

OWAS

Thoraxlumbal

spine Upper limb Hands Lower limb Head

1.1 1.2 1.3 1.4 2.1 2.2 2.3 2.4 3.1 3.2 3.3 4.2 4.3 4.6 5.1 5.2 5.3 5.4 5.5

10

20

30

40

50

60

70

80

90

100

Legend for Table 3:

- changes are not needed - changes needed immediately

- changes needed in near future - needed intensive observation

Tab. 3. OWAS – review table of recommended measures

An example of simulation for the saleswoman’s movements when taking the

shirt from the shelf is shown in Fig. 8 with the detailed results of OWAS analyses on

the right. Body posture ‘both arms above shoulder’ is signed with yellow which

means that changes are needed in the near future and the message is written: ‘The

work posture may have harmful effects on the musculoskeletal system.’

%

0

20

40

60

80

100

120

1.1. 1.2. 1.3. 2.1. 2.2. 2.3. 2.4. 3.1. 3.2. 3.3. 4.2. 4.3. 4.6. 5.1. 5.2. 5.3. 5.4. 5.5. 6.1.

Pe

rcen

tage

%

Body postures

Measured

Allowed


a. Both arms near body – normal position

b. Both arms above shoulder – the posture may have harmful effects

c. Both arms above shoulder – the posture may have harmful effects

Fig. 8. Computer aided performed OWAS analysis

6. Proposal for working positions’ improvements

Following the results from the OWAS method some changes needed to be made in the near future. The greater problems are those shelves placed relatively high and therefore the reaching of pieces at higher places is impossible without a ladder. In spite of that some solutions are possible but by greater effort and changes. Different solutions for high shelves exist within manufacturing that could also be used within the clothing shop. The idea of a movable shelves system within or without a wardrobe is one of them. The working principle is shown in Fig. 9. Shirts and


chemise could be put on shelves fixed within the movable system. In that way the saleswoman could stop the system when the desired shirt or chemise moves passed and could then take it from the shelf without uncomfortable body positions.

OWAS Analysis for ‘normal’ body position:

Fig. 9. The principle of the moving shelves system in clothing shop

7. Conclusions

Poorly designed workplace may have long-term negative consequences which,

from the perspective of the employer, are reflected in diminished sales power and

from the perspectives of the employees in workers' health difficulties (e.g. spine

damages, eye problems, etc.). It is very important from this point of view as to how a

workplace is designed and organized.

In the paper the working environment within clothing shop was researched with

the focus on a well-ordered workplace, which in accordance with the principles of

ergonomics must be adapted to a human's physical and mental needs at a minimum

effect on his/her health.

Regarding results of the OWAS observational method we concluded that work

on the observed workplace was moderately difficult, as is evident from the analyses

of postures and from the corresponding histogram. The admissible limits of the

monitored saleswoman were exceeded at five positions, and actions were needed

within reasonable time, which meant that in the future some changes would be

needed. The similar results were gained also using computer aided simulation.

During the saleswoman's work the real layout of working desks, shelves,

lighting, and positions of a particular shop were compared to the recommended

positions of the body. It was concluded that in the shop the layout of the working-

counters was appropriate, whilst some shelves were placed either too low or too high.

The greater problems were those shelves placed relatively high and therefore

reaching pieces in higher places was impossible without a ladder. To prevent the

worker from awkward body postures an innovative system with moving shelves was

proposed. This solution would be a transfer from the industrial environment where


warehouses with moving shelves are used when overhead work is necessary. The

presented solution would, of course, have to be adjusted and designed for the clothes

shop environment.

Workplace analysis considering working environment show that measured

values of noise, temperature and air velocity are within recommended values except

illumination where the measurements showed that the lighting was very high but this

could be considered as a measure for raising the atmosphere ambience within the

shop. When measuring a shirt it is also important to have suitable lighting for better

judgment regarding the shirt’s color and suitability.

8. References

Aghazadeh, F.; Mokrani, M.; Al-Qaisi, S.; Ikuma, L. & Hassa, M. (2011/2012).

Effect of overhead lifting on neck and shoulder muscle activity and upper extremity

joint angles. Occupational Ergonomics, Vol. 10, pp. 165 – 174

Andrejiova, M.; Kralikova, R.; Wessely, E.; Sokolova, H. (2012). Assesment of the

Microclimate in the Work Environment, Chapter 42 in DAAAM International

Scientific Book 2012, pp. 509-516, B. Katalinic (Ed.), Published by DAAAM

International, ISBN 978-3-901509-86-5, ISSN 1726-9687, Vienna, Austria, Doi:

10.2507/daaam.scibook.2012.42

Garg, A.; Hegmann, K.; Kapellush, J. (2006), Short-cycle overhead work and

shoulder girdle muscle fatigue. International Journal of Industrial Ergonomics, Vol.

36, No. 6, pp. 581 – 597

Grieve, J. & Dickersond, C. (2008). Overhead work: identification of evidence –

based exposure guidelines. Occupational Ergonomics, Vol. 8, no. 1, pp. 53 – 66

Harcombe, H.; McBride, D.; Derrett, S. & Gray, A. (2009). Prevalence and impact of

musculoskeletal disorders in New Zealand nurse, postal workers and office workers.

Australian and New Zealand journal of public health, Vol. 33, pp. 437-441

Nussbaum, M.; Clark, L.; Lanza, M. & Rice, K. (2001). Fatigue and endurance limits

during intermittent overhead work. American Industrial Hygiene Association

Journal, Vol. 62, No. 4, pp. 446 -456

Polajnar, A.; Leber, M. & Vujica Herzog, N. (2010). Muscular-skeletal diseases

require scientifically designed sewing workstations. Journal of Mechanical

Engineering, Vol. 56, No. 1, pp. 31-40

Rosecrance, J.; Rodgers, G. & Merlino, L, (2006). Low back pain and

musculoskeletal symptoms among Kansas Farmers. American Journal of Industrial

Medicine, Vol. 47, No. 7, pp. 547-556

Spyropoulus, E.; Chroni, E.; Katsakiori, P. & Athanassiou, G. (2013). A quantitative

approach to assess upper limb fatigue in the work field. Occupational Ergonomics,

Vol. 11, pp. 45-57

Warming, S.; Precht, D. M.; Suadicani, P. & Ebehoj, N. E. (2009). Musculoskeletal

complaints among nurses related to patient handling tasks and psychosocial factors-

based on logbook registration. Applied Ergonomics, Vol. 40, pp. 569-578

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